We're gonna turn out of the latest -- -- on Martin's seventeen year old was shot and killed by -- neighborhood watch captain exactly one month ago. And today to 75000. People expected to turn out in Sanford Florida to mark the day but the watch captain -- and -- right there is still in hiding right now. We hear from his close friend and attorney in just a minute first. -- she's -- -- joins us from San for the new accounts that may bolster Zimmerman defense good morning Matt. Hey good morning -- you mention it's been a month since -- -- -- was killed last night we got to speak with the lead prosecutor in this case. Who says she knows -- -- Martin's parents need answers but this is not a slam dunk case and it could be weeks before. And if charges are brought against George -- This morning despite the -- -- Clinton for his arrest. The lead prosecutor in the tree -- Martin's case exclusively tells ABC news -- his killer George Zimmermann. Won't be easy. Florida's stand your ground law gives enormous leeway for people like Zimmerman to use deadly force if they feel threatened. The stand your ground law is one portion of justifiably so deadly force and what that means is that the state must go forward and be able to prove. Its case beyond a reasonable doubt. Zimmerman told police he acted in self defense the night he shot the -- armed seventeen year old. In -- others are supporting those claims in eyewitness just coming forward. He's giving an entirely new account of that night telling ABC news as the two scuffled Morton. -- -- -- Voice pleading for help -- on this 911 called. He Zimmerman in fact his lawyer says it's -- remains nose was broke it. And his hid bloody somehow. Zimmerman separates the fighters that single deadly shot into Martin's chest police arrive in question Zimmerman who was never arrested. And it's that fact that Zimmerman is still walking free responded dozens of protests across the country. For -- on the hill in the nation's capital to Los Angeles too little Sanford Florida. Children athletes like the entire Miami Heat team donning the -- and in so many churches a clear message. Although it was a good news. -- And tens of thousands George are preparing to gather here in Sanford today to protest what they believe was. Brian I hate crime of course now the Department of Justice is getting -- on is investigating this as a possible hate crime. The burden of proof is -- -- will have to prove that George Zimmermann specifically targeted Martin because of his color.

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